Erosion resistant cermet linings for oil & gas exploration, refining and petrochemical processing applications

Abstract

The present invention is directed to a method for protecting metal surfaces in oil & gas exploration and production, refinery and petrochemical process applications subject to solid particulate erosion at temperatures of up to 1000° C. The method includes the step of providing the metal surfaces in such applications with a hot erosion resistant cermet lining or insert, wherein the cermet lining or insert includes a) about 30 to about 95 vol % of a ceramic phase, and b) a metal binder phase, wherein the cermet lining or insert has a HEAT erosion resistance index of at least 5.0 and a K1C fracture toughness of at least 7.0 MPa-m 1 / 2. The metal surfaces may also be provided with a hot erosion resistant cermet coating having a HEAT erosion resistance index of at least 5.0. Advantages provided by the method include, inter alia, outstanding high temperature erosion and corrosion resistance in combination with outstanding fracture toughness, as well as outstanding thermal expansion compatibility to the base metal of process units. The method finds particular application for protecting process vessels, transfer lines and process piping, heat exchangers, cyclones, slide valve gates and guides, feed nozzles, aeration nozzles, thermo wells, valve bodies, internal risers, deflection shields, sand screen, and oil sand mining equipment.

Description

FIELD OF THE INVENTION[0001]The present invention relates to cermet materials. It more particularly relates to the use of cermet materials in fluids and solids process applications requiring erosion resistance. Still more particularly, the present invention relates to the use of hot erosion resistant cermet linings and inserts requiring superior erosion / corrosion resistance, and fracture toughness for use in oil & gas exploration and production, refining and petrochemical processing applications.BACKGROUND OF THE INVENTION[0002]Erosion resistant materials find use in many applications wherein surfaces are subject to eroding forces. For example, refinery process vessel walls and internals exposed to aggressive fluids containing hard, solid particles such as catalyst particles in various chemical and petroleum environments are subject to both erosion and corrosion. The combined properties of high temperature erosion resistance and toughness are required for linings and inserts used to...

AI Technical Summary

Benefits of technology

[0011]Numerous advantages result from the advantageous method for protecting metal surfaces in oil & gas exploration and production, refinery and petro-chemical process applications subject to solid particulate erosion with a cermet lining, insert or coating comprising: a) a ceramic phase, and b) a metal binder phase wherein the ceramic phase comprises from about 30 to about 95 vol % of the volume of the cermet lining, insert or coating and wherein the cermet lining, insert or coating has a HEAT erosion resistance index of at least 5.0 disclosed herein, and the uses / applications therefore.

[0020]Still yet another advantage of the method for protecting metal surfaces with a cermet lining, insert or coating of the present disclosure is that coatings may be formed via thermal spray processing on the metal surfaces to be protected.

Problems solved by technology

For example, refinery process vessel walls and internals exposed to aggressive fluids containing hard, solid particles such as catalyst particles in various chemical and petroleum environments are subject to both erosion and corrosion.

The combined properties of high temperature erosion resistance and toughness are required for linings and inserts used to provide long term erosion / abrasion resistance of internal metal surfaces in refining and petrochemical process units with operating temperatures above 600° F. The protection of these vessels and internals against erosion and corrosion induced material degradation especially at high temperatures is a technological challenge.

The castable alumina refractories have adequate temperature and corrosion resistance, but limited erosion resistance.

The life span of the state-of-the-art refractory liners is significantly limited by excessive mechanical attrition of the liner from the high velocity solid particle impingement, mechanical cracking and spallation.

When these bonds are upgraded with stronger direct bonding of the ceramic grains, the overall lining becomes expensive to fabricate and prone to catastrophic, brittle fracture failures.

Thin layer ceramic coatings or weld overlays of precipitation hardened alloy may also be used for high temperature erosion resistance, but are less effective than conventional chemically bonded, castable refractory linings.

Thickness and ceramic content are constrained in weld overlays and plasma sprayed coatings because the layer is applied in a molten form over a solid based metal and residual thermal / forming stresses are limiting.

Harder ceramic materials also tend to be too brittle and their lack of toughness adversely affects unit reliability.

Metal rich ceramic-metal composites, such as hard facing, may alternatively be used but fall short of the level of erosion resistance provided by the aforementioned castables because forming / fabrication techniques limit the amount of hard, coarse grained ceramics available in the microstructure.

Metal matrix composites with a higher content of hard ceramic grains have been designed with superior erosion resistance and toughness via powder metallurgy techniques for applications less than 600° F., but the current art does not provide compositions with temperature and corrosion resistance usable for advantage in refining and petrochemical process applications.

The limited hot erosion resistance of state-of-the-art ceramic rich, ceramic-metal composites such as WC bonded with Co or Ni cemented carbides is attributed to the lack the thermodynamic stability for long term, high temperature wear / erosion applications in corrosive environments.

On the other hand, precipitation hardened alloys have a stable composition in high temperature process environments, but lack the high concentrations of hard ceramics and / or the shape and sizing of the these aggregates to optimize protecting the less wear resistant metal binding component from erosion.

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